Generally, pressure vessels are structures capable of containing a fluid, e.g., liquids, liquefied gases, compressed gases, and combinations thereof, under pressure. Exemplary pressure vessels include storage containers (e.g., fuel tanks, portable gas (e.g., oxygen) storage bottles, and accumulators) as well as pipes and other conduits that may be used to transport fluids at elevated pressures (e.g., hydraulic lines) and structures exposed to transient elevated pressures (e.g., rocket motor casings and launch tubes).
Traditionally, pressure vessels were made of metal. While many factors affect material selection including thermal stability, corrosion resistance, and fatigue performance; decreasing the weight, improving the burst strength, and increasing the useful life have become significant factors for pressure vessel designers. These demands have led to an increased use of fiber-reinforced composites in the construction of pressure vessels. However, still greater reductions in weight and improvements in strength are desired.